Why are you referring to this Emily like we all know her?
... But seriously, for the same reason you refer to 'x' in Python like it's already defined. It's just a symbol.
"I recently bought an iPhone 4 for my wife Emily"
"I recently bought an iPhone 4 for my daughter Emily"
"I recently bought an iPhone 4 for my dog Emily"
>>> Emily
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'Emily' is not defined